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bfs_predecessors¶

bfs_predecessors
(G, source)[source]¶ Return dictionary of predecessors in breadthfirstsearch from source.
Parameters: G : NetworkX graph
source : node, optional
Specify starting node for breadthfirst search and return edges in the component reachable from source.
Returns: pred: dict
A dictionary with nodes as keys and predecessor nodes as values.
Notes
Based on http://www.ics.uci.edu/~eppstein/PADS/BFS.py by D. Eppstein, July 2004.
If a source is not specified then a source is chosen arbitrarily and repeatedly until all components in the graph are searched.
Examples
>>> G = nx.Graph() >>> G.add_path([0,1,2]) >>> print(nx.bfs_predecessors(G,0)) {1: 0, 2: 1}